Survival and growth performance of the japanese scallop Patinopecten yessoensis seeds produced in the upper tolerant temperature
The Japanese scallop (Patinopecten yessoensis), a cold-tolerant bivalve, is one of the key species cultured in suspension on the Gangwon coast of the East Sea (Sea of Japan). However, since the commencement of the scallop farming in early 1990s mass mortalities occurred most probably due to daily te...
Main Authors: | , , , , , , , |
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Format: | Conference or Workshop Item |
Language: | English |
Published: |
2008
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Subjects: | |
Online Access: | http://irep.iium.edu.my/38545/ http://irep.iium.edu.my/38545/ http://irep.iium.edu.my/38545/1/WAS_2008-MM_Rahman_-2.pdf |
Summary: | The Japanese scallop (Patinopecten yessoensis), a cold-tolerant bivalve, is one of the key species cultured in suspension on the Gangwon coast of the East Sea (Sea of Japan). However, since the commencement of the scallop farming in early 1990s mass mortalities occurred most probably due to daily temperature variation during summer. The East Sea Fisheries Research Institute (ESFRI) monitored the scallop mortalities for years, finding that hatchery-based seeds are more resistant against the daily temperature variation than wild seeds. Noticeable difference of hatchery-based seeds from wild ones are maternal selection and higher temperature to which their larval lives are exposed. ESFRI established a method producing the scallop seeds in mass at elevated temperature 182higher than previous temperature and found it more effective for survival in the nursery and thereafter on-going growth.
We extended the hatchery water temperature up to 21to produce about 300 millions of just settled P. yessoensis larvae and compared with those produced at moderate temperatures (14, 16, and 18in terms of both survival and growth performance in the hatchery and in the ensuing nursery ground. The hatchery larval survival at 21was competitive with or even higher than that at 18However, a great mass mortality occurred for the larvae of 21during temperature acclimation to wild temperature, an intermediate step prior to translocaton to nursery ground. The mortality lasted 15 days post settlement, resulting in a total of around 90% mortality, which was greater than that of other temperatures. The spat survivals, thereafter, were stable until second mortality happened during another translocation process to mesh size-bigger lantern cages (Figure 1). Larval and spat growths were also serially measured to compare along with their survivals.
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